1. Field of the Invention
The field of the invention is that of in-line filters, that is, filters constructed to be coupled into an air or gas line for filtering. Generally these filters are of the type having a casing with end fittings which can be coupled into an air or gas line with a cartridge within the casing.
2. Description of the Prior Art
Filters of general or typical type as identified above, are well known in the art. Such filters normally include a cylindrical casing made of metal or other material with end fittings which can be coupled into an air or gas line, the end fittings being held together by holding rods having bolts or wing nuts at one end. These devices as known in the prior art are subject to significant disadvantages and drawbacks. Firstly, in order to replace the filter element or cartridge in the unit, the whole structure has to be disassembled, that is, it has to be uncoupled from the fluid line, the end fittings removed and then the cartridge taken out of the filter casing. This is, or course, a cumbersome and time consuming procedure, and, of course, leaves room for substantial improvement by way of a device that can eliminate the necessity.
A further area in which there was room for improvement in the prior art, resided in the use of a cartridge that is typically in the form of, for example, a couple of flexible bags containing the filter material, which might be comminuted clay material. Such bags had to be folded and creased in order to get them into the casing and then they had to be compressed together at the end for possibly about an inch in order to get them in, which became very difficult, time consuming and once they were in, the longitudinal crease in the bags tended to allow fluid to pass through the filter which remained contaminated. Thus, there has existed a need for an improved cartridge that could be more easily replaced in the filter, without folding and creasing and without degrading the capability of the filter to successfully filter the air or gas passing through it.
The herein invention, a preferred form of which is described in detail herein, is intended to overcome the above described drawbacks of the prior art as well as to provide additional capabilities and advantages.